Preheat oven to 375 degrees. Make a paste from the olive oil, seasonings, orange zest, and orange juice. Spray a casserole dish with cooking spray (choose one large enough for the chicken to rest with some space between the pieces.) Arrange mushrooms in the bottom of the pan, then place chicken on top of the mushrooms. Brush or spoon the spice paste over the chicken, making sure to coat all. Pour any additional paste on the chicken and mushrooms and stir a bit to coat the mushrooms well. 

Bake uncovered until the chicken's internal temperature measures above 160 degrees using an oven thermometer inserted into the fattest part of the thickest thigh. Cooking time will vary depending on the thickness of the thighs, anywhere from 40 minutes to 1 hour.

Serve over couscous, or with mashed potatoes or pasta.